In Mac/Modules/file/_Filemodule.c UTCDateTime values are 
converted using these functions:
 
static int
UTCDateTime_Convert(PyObject *v, UTCDateTime *ptr)
{
        return PyArg_Parse(v, "(HlH)", &ptr->highSeconds, &ptr-
>lowSeconds, &ptr->fraction);
}

static PyObject *
UTCDateTime_New(UTCDateTime *ptr)
{
        return Py_BuildValue("(HlH)", ptr->highSeconds, ptr-
>lowSeconds, ptr->fraction);
}


Shouldn't the format string be "(HLH)" in both cases? The struct 
definition of UTCDateTime contains unsigned times (UInt16, UInt32 
and UInt16).

The same problem is present in Python 2.3

Closing this as won't fix. Nobody else complained and changing this might 
break existing code.